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151.
We studied the incidence of cerebral hemorrhage in an animal model of embolic stroke to determine the safety of aspirin, heparin, and tissue plasminogen activator therapies. We occluded the middle cerebral arteries of rabbits with labeled blood clots and administered either tissue plasminogen activator, heparin, aspirin, tissue plasminogen activator plus aspirin, tissue plasminogen activator plus heparin, or saline at various times after stroke. Compared to saline controls, both the aspirin-only and the tissue plasminogen activator-plus-aspirin groups had a significantly higher incidence of cerebral hemorrhage, whereas the heparin and tissue plasminogen activator combination groups did not. We conclude that aspirin antiplatelet therapy alone may increase the risk of hemorrhagic infarction, whereas heparin or tissue plasminogen activator therapy appears to be relatively safe.  相似文献   
152.
In the period 1979-1980 the following anthropometric measurements were recorded in 2351 healthy Dutch children from 0-17 years of age: height, weight, sitting height, arm span, lengths of upper-arm, lower-arm and hand, tibial length, foot length, biacromial diameter, biiliacal diameter, and head circumference. Corresponding percentile values were constructed on the basis of normality assumptions, the mean and standard deviation at age t being determined by a cubic spline approximation. The results are compared with other studies and given in the form of growth charts.  相似文献   
153.
Galanin-like immunoreactivity has been visualized in nerve fibers in the islets of Langerhans, suggesting an involvement of galanin in the neural regulation of islet function. In this study, we investigated the effects of galanin on basal and stimulated insulin and glucagon secretion by infusing the peptide at three different dose rates in rats. We also studied the direct effect of galanin on insulin secretion from freshly isolated rat islets. At 320 pmol/kg/min, but not at 20 or 80 pmol/kg/min, galanin lowered basal plasma insulin levels. In contrast, basal plasma glucagon levels were lowered by galanin already at 20 and 80 pmol/kg/min. Furthermore, galanin inhibited both glucose- and arginine-induced insulin release at all three dose levels, whereas arginine-induced glucagon release was not affected by galanin. Glucose-stimulated insulin secretion from isolated rat islets was dose-dependently suppressed by galanin (10-6-10-8M). Therefore, it is concluded that galanin in rats inhibits insulin secretion, both in vivo and in vitro, and that at lower dose levels, the peptide also inhibits basal glucagon release.  相似文献   
154.
Advanced malignant melanomas of the uvea unsuited for an eye salvaging approach require enucleation of the tumor containing eye. A series of 68 patients is reported who underwent enucleation combined with insertion of a spherical dura-encased implant after 30 Gray pre-irridiation therapy of the orbit. Postoperative results with special attention to cosmetic outcome and motility of the prosthesis suggest that the insertion of an orbital implant should be preferred to the enucleation with no implant.  相似文献   
155.
The effects of different amounts of dietary zinc on the Zn absorption rate and on Zn, calcium and magnesium concentrations in tissues of MOPC 104E tumor-bearing Balb/c mice were determined. The Zn absorption rate was inversely related to the amounts of Zn in their diets and was lower than that of nontumor-bearing control mice fed a laboratory mice chow. Zn concentrations of tumor-bearing mice were also low compared with control mice but tumor Zn concentrations, regardless of the concentrations of Zn in the diets, were higher than those of normal tissues of the host other than the pancreas. Ca concentrations in tumor and tissues of tumor-bearing mice were higher than in control animals but Mg concentrations in tissues of tumor-bearing mice appeared to be similar to those of control mice. Results suggest that tumor-bearing mice have a lower intestinal Zn absorption capacity and a higher Zn uptake rate causing other tissues to become hypozincemic and hypercalcemic.  相似文献   
156.
Rat brain hippocampal slices were incubated with or without the convulsant 4-aminopyridine (4-AP). From these slices a crude mitochondrial/synaptosomal membrane fraction was prepared and analyzed for endogenous protein phosphorylation. 4-AP (10(-5) M) stimulated the phosphorylation of a 50 kDa protein by 86%. The phosphorylation of this 50 kDa protein is Ca2+/calmodulin-dependent and we suggest that this protein is the lower molecular weight subunit of Ca2+/calmodulin-dependent protein kinase II (CaMK II).  相似文献   
157.
158.
The direct actions of phencyclidine (PCP) on mammalian sarcolemma were examined by determination of the drug's effects on the action potentials of isolated guinea-pig ventricular cells, and on the underlying ionic currents. PCP (10(-6) to 10(-4) M) did not alter the resting membrane potential but produced a dose-dependent prolongation of the duration of the action potential, and a reduction of the rate of depolarization of phase 0 (Vmax) of the action potential. Voltage clamp experiments revealed that PCP blocks both myocardial Ca++ channels and myocardial time-dependent K+ channels. The K+ channel blockade was shown to exhibit an apparent voltage-dependence. The effects of PCP on these ionic channels could explain previous reports of it prolonging myocardial action potentials and conflicting reports of positive and negative inotropism.  相似文献   
159.
160.
Based on a standardized in-vitro method for quantifying the activity of prostaglandin-synthetase by means of coupling malondialdehyde with 2-thiobarbituric acid the possibility of using this method also as ex-vivo technique is described. By this, more favourable prerequisites to pharmacological valuation of the effects of potential antiinflammatory substances exists compared to the application of in-vitro results, only.  相似文献   
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